1. Field of the Invention
This invention relates to a bearing structure for a rotating shaft that rotates a floppy disk in an electronic device such as a personal computer and a word processor or the like.
2. Related Art
A disk table is usually fixed on a rotating shaft of an electronic device of this type to integrally rotate a floppy disk carried on the disk table. Therefore, precision of rotation free from unevenness and undesired movement is required for the rotating shaft.
Specifically, as shown in, e.g., FIG. 3, a conventional bearing structure is such that a frame 12 made by aluminum die-casting or the like and a bearing section 13 for supporting a rotating shaft 11 of a motor 10 are integrally formed and that a bearing 14 and a metal sleeve 15, both fitted into the bearing section 13, rotatably support the rotating shaft 11 of the motor 10. The motor 10 is secured to the frame 12 by a bracket 16, and a disk table 17 is disposed on the upper end of the rotating shaft 11.
However, in the above-mentioned conventional bearing structure for a rotating shaft, the bearing section and the frame which support the rotating shaft are integrally formed by aluminum die-casting or the like, and to prevent eccentricity and uneven rotation of the rotating shaft, high precision is required to machine the portions into which the bearing and the metal sleeve are fitted, which in turn elevates the material cost as well as the molding cost. In addition, the operation of assembling the bearing and the metal sleeve to the bearing section has not been performed in a subline.